package com.dream.keigezhushou.Activity.kege.view;

import android.graphics.Bitmap;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;

/**
 * Created by Administrator on 2017/3/18.
 * <p/>
 * 高斯模糊
 */
public class BoxBlurFilter {

    /**
     * 水平方向模糊度
     */
    private static float hRadius = 10;
    /**
     * 竖直方向模糊度
     */
    private static float vRadius = 10;
    /**
     * 模糊迭代度
     */
    private static int iterations = 7;

    public static Drawable Filter(Bitmap bmp) {
        int width
                = bmp.getWidth();
        int height
                = bmp.getHeight();
        int[]
                inPixels = new int[width
                * height];
        int[]
                outPixels = new int[width
                * height];
        Bitmap
                bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
        bmp.getPixels(inPixels,
                0,
                width, 0,
                0,
                width, height);
        for (int i
             = 0;
             i < iterations; i++) {
            blur(inPixels,
                    outPixels, width, height, hRadius);
            blur(outPixels,
                    inPixels, height, width, vRadius);
        }
        blurFractional(inPixels,
                outPixels, width, height, hRadius);
        blurFractional(outPixels,
                inPixels, height, width, vRadius);
        bitmap.setPixels(inPixels,
                0,
                width, 0,
                0,
                width, height);
        Drawable
                drawable = new BitmapDrawable(bitmap);
        return drawable;
    }


    public static void blur(int[]
                                    in, int[]
                                    out, int width,
                            int height,
                            float radius) {
        int widthMinus1
                = width - 1;
        int r
                = (int)
                radius;
        int tableSize
                = 2 *
                r + 1;
        int divide[]
                = new int[256 *
                tableSize];

        for (int i
             = 0;
             i < 256 *
                     tableSize; i++)
            divide[i]
                    = i / tableSize;

        int inIndex
                = 0;

        for (int y
             = 0;
             y < height; y++) {
            int outIndex
                    = y;
            int ta
                    = 0,
                    tr = 0,
                    tg = 0,
                    tb = 0;

            for (int i
                 = -r; i <= r; i++) {
                int rgb
                        = in[inIndex + clamp(i, 0,
                        width - 1)];
                ta
                        += (rgb >> 24)
                        & 0xff;
                tr
                        += (rgb >> 16)
                        & 0xff;
                tg
                        += (rgb >> 8)
                        & 0xff;
                tb
                        += rgb & 0xff;
            }

            for (int x
                 = 0;
                 x < width; x++) {
                out[outIndex]
                        = (divide[ta] << 24)
                        | (divide[tr] << 16)
                        |
                        (divide[tg] << 8)
                        | divide[tb];

                int i1
                        = x + r + 1;
                if (i1
                        > widthMinus1)
                    i1
                            = widthMinus1;
                int i2
                        = x - r;
                if (i2
                        < 0)
                    i2
                            = 0;
                int rgb1
                        = in[inIndex + i1];
                int rgb2
                        = in[inIndex + i2];

                ta
                        += ((rgb1 >> 24)
                        & 0xff)
                        - ((rgb2 >> 24)
                        & 0xff);
                tr
                        += ((rgb1 & 0xff0000)
                        - (rgb2 & 0xff0000))
                        >> 16;
                tg
                        += ((rgb1 & 0xff00)
                        - (rgb2 & 0xff00))
                        >> 8;
                tb
                        += (rgb1 & 0xff)
                        - (rgb2 & 0xff);
                outIndex
                        += height;
            }
            inIndex
                    += width;
        }
    }

    public static void blurFractional(int[] in, int[] out, int width, int height, float radius) {
        radius -= (int) radius;
        float f = 1.0f / (1 + 2 * radius);
        int inIndex = 0;

        for (int y = 0; y < height; y++) {
            int outIndex = y;

            out[outIndex] = in[0];
            outIndex += height;
            for (int x = 1; x < width - 1; x++) {
                int i = inIndex + x;
                int rgb1 = in[i - 1];
                int rgb2 = in[i];
                int rgb3 = in[i + 1];

                int a1 = (rgb1 >> 24) & 0xff;
                int r1 = (rgb1 >> 16) & 0xff;
                int g1 = (rgb1 >> 8) & 0xff;
                int b1 = rgb1 & 0xff;
                int a2 = (rgb2 >> 24) & 0xff;
                int r2 = (rgb2 >> 16) & 0xff;
                int g2 = (rgb2 >> 8) & 0xff;
                int b2 = rgb2 & 0xff;
                int a3 = (rgb3 >> 24) & 0xff;
                int r3 = (rgb3 >> 16) & 0xff;
                int g3 = (rgb3 >> 8) & 0xff;
                int b3 = rgb3 & 0xff;
                a1 = a2 + (int) ((a1 + a3) * radius);
                r1 = r2 + (int) ((r1 + r3) * radius);
                g1 = g2 + (int) ((g1 + g3) * radius);
                b1 = b2 + (int) ((b1 + b3) * radius);
                a1 *= f;
                r1 *= f;
                g1 *= f;
                b1 *= f;
                out[outIndex] = (a1 << 24) | (r1 << 16) | (g1 << 8) | b1;
                outIndex += height;
            }
            out[outIndex] = in[width - 1];
            inIndex += width;
        }
    }

    public static int clamp(int x, int a, int b) {
        return (x < a) ? a : (x > b) ? b : x;
    }

}
